Friday, September 30, 2005

I’ve now completed the initial batch of 10 lead ballast pigs, each weighing about 11.5 kilos; that leaves me with a choice as to what I should do next.

If only the weather would stabilize into a warm dry spell, I’d be able to have a go at the mast. The problem is that most of my building efforts have to be done outside on the driveway, because there just isn’t enough room in the garage as it’s set out at the moment. Even the wood and plywood for building the hull is taking up far too much space. Somehow, I’ll need to solve the storage deficiency so that I’ll be able to have room for making things in the garage during the winter.

Because my efforts have been on finishing the ‘10 little pigs’, I’ve not completed the rudder and stock, which both need to have their surfaces smoothed before being yoked together with a nut and bolt. I’ll not be fixing the tiller to the stock until I can be sure of the exact position by trying it out when the hull has been assembled.

Thursday, September 29, 2005

I had a surprise while heating lead for the seventh pig, when a hole suddenly appeared in the much used saucepan and lead poured onto the concrete driveway leading to my garage. As usual I was using two heat sources: the gas ring and a blow torch, both of which I immediately turned off. This meant I had to buy another saucepan about the same diameter and depth as the broken one. The cheapest I could find that would do the job was just under £10.00! Most were in the region of £18.00.

As I was driving home from the shop where I bought the saucepan it dawned on me that it was made from aluminium, which, when under extreme temperature, can catch fire, as a warship in the Faulkland war did after being hit by a missile.

Nevertheless I went ahead and melted lead in the new saucepan and it showed no signs of bursting into flame, but I did take the precaution of heating it only on the gas ring.

The average weight of the ballast pigs is 11.5 kilos and with a minimum of 10, that’ll bring the fixed ballast to 115 kilos, 65 kilos less than the maximum permitted according the boat plans.

Tuesday, September 27, 2005

My prognostications about having to buy at least another two bread pans for moulds may prove pessimistic, as I've now made six lead ballast pigs with the original bread pan - even the saucepan is holding out, although its metal has somewhat fatigued.

By using two heat sources concurrently I've been able to bring the waiting time down for casting a pig to 50 minutes. To help speed up the process I created a shelter for the heating area with one of those wind brakes found on beaches, because the cooling effect of the wind can be significant.

Practice makes perfect - so the saying goes - and by repetition I've been able to improve my lead cutting technique when making small bits of it by using a pair of old garden shears. While standing before a bench I first cut strips from the flashing about 2 inches wide which I subsequently chop into pieces about an inch wide. As the lead melts in the saucepan I add pieces until there's enough to fill the mould.

After casting four more pigs, bringing the total to ten, I'll not make any more until I may need them for trimming the boat. Each pig has to be firmly secured to the floor of the boat in a specific position according to Matt's design – I'll be saying more about this when the time comes.

I'm uncertain what to tackle next after casting the tenth pig, because I shall be using epoxy which requires a reasonably warm temperature, say 15 degrees Celsius or more, and autumn is fast approaching bringing distinctly cooler weather. Of the smaller pieces remaining to build there are the mast, spars and the stem, but I've yet to finish the rudder and stock by applying a final coat of epoxy to bring about a smooth surface.

Saturday, September 24, 2005

With the aid of a new burner powered by a 907 cartridge of Calor Gaz it only took an hour to melt and cast a pig of lead weighing about 12 kilos, but the bread pan in which the pig was made already shows signs of deterioration. It has two bumps which I inadvertently did when extricating the cold lead by the use of a wooden mallet. At this rate I’ll have to buy at least another two pans for casting seven more pigs for the completion of my initial batch of ten.

Take the time to weigh the lead which should be chopped into small pieces before casting the first pig. When the lead is fully molten and the dross floating on the top has been removed with a wooden spoon, make a mental note where the level of the lead is on the saucepan; that will enable you to make subsequent pigs all the same weight without the need to weigh the lead – simply keep adding lead until the correct level is reached, and use gloves to avoid contact with it, as lead is poisonous by absorption through the skin.

For thin lead such as the sheet type used for flashing tiles on roofs, cut it into small pieces with old garden shears, but for more solid lead like old plumbing pipes, saw them into manageable bits by means of a band saw with large teeth; note that saws with small teeth, such as hacksaws, are not a bit of good for the job because they clog up and jam. To help saw lead more easily lubricate the blade with ordinary oil.

Make sure your saucepan for melting the lead is not too large for the burner; otherwise the lead will remain cool on the sides of the pan where the heat cannot reach by conduction. I discovered this when I tried to melt lead in a large galvanized bucket. Also allow the first small quantity of lead to melt thoroughly before adding more lead. As the bulk of it becomes molten, more and more un-melted lead can progressively be added until the final amount is arrived at.

A saucepan with two handles is better than one having a single handle, because it is easier to control and lift when pouring the molten lead slowly into the mould. By the way, dig a hole in the ground the exact size and shape of the bread pan, so that it can be supported horizontally with no chance of spilling the liquefied lead.

Your lead will melt more quickly if the pan is covered with a lid which can also be used as a shield when adding more lead to protect your eyes from spattering. As an additional precaution, wear goggles.

Friday, September 23, 2005

Yesterday I only managed to produce one lead ballast pig, but not after a struggle, because the wind and ambient temperature conspired together to prevent the lead melting; the main reason for ineffectual heating was the inadequate power source – in truth the Butane painter’s torch. Accordingly, today I bought a proper single burner from Camping and General that can be powered by either Butane or Propane.

Perhaps tomorrow I may be able to find time for making my third lead pig. I may also finish applying epoxy to the rudder and stock.

Tuesday, September 20, 2005

Apart from drilling the holes for the bolt holding the rudder in place and finishing them to prevent water ingress, I’ve almost completed the rudder and stock; only the final coat of thickened epoxy needs applying, but not before I’ve smoothed their surfaces by using fine sandpaper. Because each side of the rudder and stock have to be done separately, it’ll be another two days before they can be finished. Of course, the time will arrive when the whole of the boat’s exterior will need painting, including the rudder and stock; however that’s not likely to come about until next year, or perhaps 2007! It depends on how much time I can put aside for building her.

In line with my plan to make as many of the small items I can before assembling the hull, I cast the first pig of lead today. To begin with, I did not have much success in getting the lead to melt, because I used a galvanized bucket that was far too large for the Butane painter’s torch to heat up. I therefore resorted to using the saucepan in which I had heated the lead rudder weight; this was satisfactory, but I had to hold the rim of the saucepan with a mole grip in my left hand while I held the handle of the saucepan with my right hand as I carefully poured the molten lead into a bread pan; both hands were required because of the weight of the lead.

Taking Don Elliott’s advice, I had previously set the bread pan in the earth level with its brim to help absorb heat from the pan and to give it support. Don suggests that initially one should make eight of these pigs, but as my first one weighs 10 kilos, I think I should cast ten of them, bringing the total fixed ballast to 100 kilos; then if I should need more for trimming the boat, I’ll be able to do them at my leisure. Matt’s plans indicate there should be between 70 and 180 kilos of ballast.

Saturday, September 17, 2005

After adding more tape around the edges of both the stock and rudder I gave them a day to harden; then I smoothed uneven surfaces with a course, flat file. In preparation for skimming the surfaces with thickened epoxy I lightly abraded them with the same file. Afterwards I used a squeegee to spread the epoxy so as to fill minute hollows between the weave and the weft of the woven roving. Where it was not possible to use the squeegee, such as the forward facing area of the stock, I used a paint brush to apply an even layer of thickened epoxy.

As this was the first time I’ve tried the technique I await with some apprehension the result when it has hardened. How much sanding will be needed to make surfaces really smooth, and how many more coats, if any, will be necessary to bring about a professional finish? That remains to be seen.

I can anticipate several days passing before both the stock and the rudder will be finished; that’s not because there’s a lot to be done, but because between each application of epoxy I have to wait at least 24 hours.

Such a process could well go in parallel with making other parts of the boat the same day, but demands on my time often do not permit it. Unless the weather is warm and fine, and I am able to spend more time on the project, I can see building my dream boat will take a fair while.

Thursday, September 15, 2005

When I started making the rudder and stock I did not realize how much work would be needed to complete them. Shaping them from plywood took long enough, and now I am sheathing them with one coat of 6 oz woven roving. I’ve used fibreglass tape to wrap around sharp edges.

In practice it is not supposed to be possible to make woven roving bend around a sharp edge, but thin tape will sit quite well on a 90 degree turn, providing there is just a little convex curvature along the edge. Where there’s an absolutely sharp 90 degree turn at an edge, then I agree woven roving cannot be made to conform to adjacent surfaces.

One trick I have found useful is to wait ten or fifteen minutes after softening the tape or woven roving at the edges with epoxy, then make it comply with the form by pushing and prodding it with a brush. Even five hours after applying epoxy when it is dry to the touch, woven roving can be squeezed or pushed into place with ones fingers.

When all surfaces of the rudder and stock have been sheathed, I’ll need to wash them with a little detergent; then after they are dry, I’ll have to fill the small cavities that naturally occur within the woven roving. To do this I’ll use soft filler powder mixed with epoxy, applied with a squeegee.

Finally, I’ll attach the upper pintle, but that cannot be done until I am certain where to fix it, and that will not be possible until the transom is in place and the lower special gudgeon has been fixed to it.

Monday, September 12, 2005

In the building manual produced by Don Elliott for the Paradox there are instructions for making a sander from plywood; it uses 3 inch wide sandpaper from an electric belt sanding machine. I made my own according to Don’s design and it works well.

When the rudder and stock have been glassed and the woven roving has been filled and smoothed, I’ll use the sander to bring about a good finish before coating them with epoxy.

To see a picture of the sanding tool, please visit http://www.smallsailboats.co.uk/paradox/con_gallery.htm .

Saturday, September 10, 2005

Yesterday I smoothed the lead in the rudder by using a course file and sandpaper; then I filled any irregularities with thickened epoxy. A photo of the finished weight will be posted to http://www.smallsailboats.co.uk/paradox/con_gallery.htm where I am keeping a visual record of how I am building my Paradox micro-sailboat.

Today I made one of Don Elliott’s special tools for building Paradox; it was a sanding board utilizing belt-sander strips. It’s made from half inch plywood 16.5 inches long and 3 inches wide. There are two stout handles at either end so that the user can enter into a rhythm when sanding flat surfaces such as the GRP sheathing and epoxy filler that encapsulates the hull and rudder. This tool can also be used for rounding edges prior to sheathing them.

Next week I’ll be able to test my skills at applying the GRP sheathing to the rudder and stock. I have bought a squeegee for distributing the epoxy evenly throughout the woven roving and for applying the epoxy filler. I have an angle grinder with a 60 grit sheet, which should be ideal for sanding any rough irregularities caused by poor application.

Thursday, September 08, 2005

I managed to cast the lead weight in the trailing edge of the rudder today.

Before casting the lead I had to cut out the shape from the profiled rudder according to the plan; then I screwed in 6 screws as retainers for the lead. I made a mould from a piece of oak plank and a strip of soft wood. The rudder was laid on its side and the mould was clamped under the cavity to form a reservoir for the lead. Where the trailing edge was rounded I filled the gaps between it and the mould with wooden wedges. Before pouring the molten lead I supported the blade so that the upper side was horizontal by using a spirit level.

The designer, Matt Layden, calculated I would need 3 kilos of lead, which proved to be accurate.

My lead was melted by the flame of a painter’s Butane torch placed under a saucepan which was supported on two bricks; the lead was ready to pour after 15 minutes.

Tomorrow I may be able to shape the lead to follow the blade’s profile and touch up any irregularities by using thickened epoxy.

That would bring me to the stage where I’d be able to sheath the blade and its stock with GRP in the form of 6 ounce woven roving and epoxy filler.

Tuesday, September 06, 2005

Today I completed all the woodwork for the rudder and stock. I must cut out a section in the trailing edge of the rudder for the lead weight; then I’ll need to form a mould there made from wood before melting 3 kilos of lead to make the weight.

When the lead has cooled and has been smoothed to the correct profile, I’ll be able to apply fibreglass to protect the rudder from the elements; likewise the boat plans require me to cover the stock with fibreglass.

What to do next, I’m uncertain, but the weather and necessary duties during the next few days will determine the outcome.

Monday, September 05, 2005

After sanding the stock, complete with its boarding step, I cut out two pieces of 12 millimetre plywood according to the design for the rudder. These I bonded together with epoxy - this was done after I shaped the groove for the lifting line.

Tomorrow I may be able to give the rudder a classic foil section, but the upper part on the port side I’ll need to keep flat, to provide a better bearing surface against the stock.

When the rudder has been shaped in section I’ll cut out a notch on the trailing edge for casting 3 kilos of lead which will be held in place with screws.

In addition to working on the rudder I managed to draw out the forward side piece of the hull from the same plywood I used to make the rudder.

All, in all, I’m pleased with my progress, but from Thursday onwards the forecast is for rain until the weekend; therefore I need to do as much as I can tomorrow and the following day.

Saturday, September 03, 2005

There’s a lot more work in building the rudder stock than I anticipated. Today I was able to spend a few hours making the boarding step, which will be bonded to the bottom of the stock on the port side.

I don’t anticipate swimming off the boat too often, and neither do I expect to fall in the water, because most of the time when afloat I should be in the cabin, but when launching off a shallow ramp or beach the boarding ladder should be most useful. The lower part of the stock may provide steerage when underway in very shallow water.

I tried to make the step as streamlined as possible without compromising strength. Its upper side is flat, except for the leading edge, but the underside has a classic foil section. The whole thing will be underwater and, like the rudder and the stock, it will be encapsulated in fibreglass cloth to prevent water ingress and to provide extra strength.

Tomorrow I may be able to finish shaping the rudder stock and attaching the step.

Friday, September 02, 2005

If you’ve been following this ‘blog’ you will know the current subject matter is about the building of a Paradox micro-sailboat. This is a highly specialized topic, but for those interested in the little boat, nothing could be more absorbing. Builders of Paradox share with one another at two Internet discussion groups: http://groups.yahoo.com/group/paradoxbuilders/ and http://groups.yahoo.com/group/Paradoxboatbuilders/ . They compare building techniques, seek advice from those who have ‘been there before’, and report on their progress. Resources within the groups comprise photographs illustrating various aspects of the building process, notes on techniques and materials, and articles about the boat and her performance.

I started building my Paradox just under a month ago, and to date I have finished laminating all the beams, including the cabin and hatch beams. I’ve also made the tiller. Today, I’m working on the rudder stock, which is made from two pieces of 18 mm plywood. The purpose of the stock is to support the kick-up rudder. Like everything on this boat, her specification is much more than adequate; in fact, if there is a criticism of Matt Layden’s design, she is well over-built in terms of strength. For her overall length of 13’ 10” she is exceedingly heavy, but being a heavy displacement vessel also means she’s more comfortable to sail, although more ponderous than her lightweight counterparts.

At the base of the rudder stock there is a massive bronze rod acting as a pintle and at the upper end of the stock there is a traditional pintle, also made from bronze. Each of these are designed to fit gudgeons on the transom, but the lower one, instead of being cast in bronze will be made according to Matt’s design from chopped strand matt, woven roving and epoxy. Both the rudder and the stock will be encased in a layer of glass reinforced plastic (GRP). The GRP will not only increase the strength of the structure, but it will protect the plywood from the detrimental effects of the elements.

I cut the two pieces needed for making the rudder stock from a sheet of 18 mm marine plywood, and from the same sheet I also cut bulkhead number three. There’s sufficient left of the original piece of plywood to make the front end of the bottom of the boat.

After shaping and sanding the rudder stock pieces, I bonded them together with the bronze rod pintle embedded between them in two semicircular gullies, one in each cheek of the stock. By using gullies I avoided having to drill a straight hole through the stock to receive the pintle.